Fights of logic in a vacation

Scene - 1
Vacationing in Sringeri (a Jyotirmath) and on a dip in the nearby river of Tunga.
Scene - 2
Perfectly undressed (with the undergarments on, I mean) man jumps for the water with shampoo on his hands, waiting to be applied on his head.
Scene - 3
Lets call the man, TM (troublemaker). TM's wife (TMW) calls out loud in an endearing tone (for her husband) which more than reveals a fear inside (of the guard sitting beside) and says

TMW - TMji don't use shampoo or soap, otherwise the guard will do some galatta (create a scene)
TM - No it does not matter (and rinses his hair and his action is perfectly coordinated with the movement of the guard's neck away from the river)

Me - Sir, please don't do that. Like you there are zillions, like me, who like to and love to take a holy dip in these waters (and do their pujas etc).
TM - How much difference (damage he should have said) can the amount of shampoo, on my head, can make?
Me - (Boom, baah, bust) I mumble. Can I say that the 8 grams of shampoo on your head causes a damage of Rs. 1000 worth of aquatic life.

Lessons learnt -

1. Economics - Had it worked?
   
2. People - Only driven by fear, ruckus and not logic.
   
3. Education - My education is not helping me and most importantly his education is not making him aware as well.
   

What the heck?